A capacitive touch sensor may comprise a matrix of electrically conducting column and row electrodes, with electronics to measure the capacitance from each row to each column. Depending on the electrode geometry, the proximity of a user's finger or other object may cause a change in that capacitance. When used with a display device, a capacitive touch sensor is typically attached to the user-facing surface of the display, to maximize the signal-to-noise ratio of the capacitance-change measurement. To avoid obstructing the user's view of the display panel, the sensor's electrodes may consist either of an optically transparent, electrically conductive material, or of an opaque electrically conductive material of low areal solidity, such as a mesh of narrow metal conductors. Because the available transparent conductive materials have relatively low electrical conductivity, metal-mesh electrodes are presently favored for capacitive touch sensors requiring electrodes exceeding roughly 0.5 meters in length. However, any superposition of two or more unlike periodic structures, or of identical periodic structures having a relative angular displacement, will produce perceptible moiré patterns.